Friday, 24 April 2015

finished work station. Peter

The final result of the build with the camera built into the coffee cup. The Mbed is shown at the back of the table where the arduino controlling the eyes is built into the box at the back of the table to hold the microcontrollers. The sonar is mounted to the front of the table.A regulated 5v  power supply capable of driving the 3 servos was needed. The eyes were 8x8 led matrices from Adafruit. These leds came as a kit with a driver to control the leds over I2C, some soldering needed to be done. The leds came from http://shop.pimoroni.com/products/small-1-2-8x8-bright-square-led-matrix-backpack.A vero board was then used to mount the 'eyes' with a diode to prevent incorrect power connection. With using I2C, pull up resistors of 4.7K (when using 5v power supply) are used for the data (sda) and the clock (scl). The servo for raising and lowering the head was installed under the lamp with a wire attached to the pully on the servo. Information on the led matrix can be found from Adafruit https://www.adafruit.com/categories/326 and the code for the eyes came from https://github.com/adafruit/Adafruit-LED-Backpack-Library/blob/master/Adafruit_LEDBackpack.cpp  
The issue with the camera was with the angle needed to clearly follow a person, this was in part due to the height of the table. Using the cup upright wouldn't allow the ideal angle, by placing the cup on its side, although this wouldn't allow the correct height, it did allow the correct angle.

Regards Peter.

No comments:

Post a Comment